libvips/libsrc/format/im_vips2png.c

322 lines
6.9 KiB
C

/* Convert 1 to 4-band 8 or 16-bit VIPS images to/from PNG.
*
* 28/11/03 JC
* - better no-overshoot on tile loop
* 22/2/05
* - read non-interlaced PNG with a line buffer (thanks Michel Brabants)
* 11/1/06
* - read RGBA palette-ized images more robustly (thanks Tom)
* 20/4/06
* - auto convert to sRGB/mono (with optional alpha) for save
* 1/5/06
* - from vips_png.c
* 2/11/07
* - use im_wbuffer() API for BG writes
*/
/*
This file is part of VIPS.
VIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
/*
#define DEBUG
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <vips/intl.h>
#ifndef HAVE_PNG
#include <vips/vips.h>
int
im_vips2png( IMAGE *in, const char *filename )
{
im_error( "im_vips2png", _( "PNG support disabled" ) );
return( -1 );
}
#else /*HAVE_PNG*/
#include <stdio.h>
#include <assert.h>
#include <stdlib.h>
#include <vips/vips.h>
#include <vips/internal.h>
#include <png.h>
#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/
#if PNG_LIBPNG_VER < 10003
#error "PNG library too old."
#endif
static void
user_error_function( png_structp png_ptr, png_const_charp error_msg )
{
im_error( "im_vips2png", _( "PNG error: \"%s\"" ), error_msg );
}
static void
user_warning_function( png_structp png_ptr, png_const_charp warning_msg )
{
im_error( "im_vips2png", _( "PNG warning: \"%s\"" ), warning_msg );
}
/* What we track during a PNG write.
*/
typedef struct {
IMAGE *in;
im_threadgroup_t *tg;
FILE *fp;
png_structp pPng;
png_infop pInfo;
png_bytep *row_pointer;
} Write;
static void
write_destroy( Write *write )
{
IM_FREEF( im_threadgroup_free, write->tg );
IM_FREEF( im_close, write->in );
IM_FREEF( fclose, write->fp );
if( write->pPng )
png_destroy_write_struct( &write->pPng, &write->pInfo );
IM_FREE( write->row_pointer );
im_free( write );
}
static Write *
write_new( IMAGE *in )
{
Write *write;
if( !(write = IM_NEW( NULL, Write )) )
return( NULL );
memset( write, 0, sizeof( Write ) );
if( !(write->in = im__convert_saveable( in, IM__RGBA )) ) {
im_error( "im_vips2png",
"%s", _( "unable to convert to RGB for save" ) );
write_destroy( write );
return( NULL );
}
write->tg = im_threadgroup_create( write->in );
write->row_pointer = IM_ARRAY( NULL, write->tg->nlines, png_bytep );
write->fp = NULL;
write->pPng = NULL;
write->pInfo = NULL;
if( !write->tg || !write->row_pointer ) {
write_destroy( write );
return( NULL );
}
if( !(write->pPng = png_create_write_struct(
PNG_LIBPNG_VER_STRING, NULL,
user_error_function, user_warning_function )) ) {
write_destroy( write );
return( NULL );
}
/* Catch PNG errors from png_create_info_struct().
*/
if( setjmp( write->pPng->jmpbuf ) ) {
write_destroy( write );
return( NULL );
}
if( !(write->pInfo = png_create_info_struct( write->pPng )) ) {
write_destroy( write );
return( NULL );
}
return( write );
}
static int
write_png_block( REGION *region, Rect *area, void *a, void *b )
{
Write *write = (Write *) a;
int i;
/* Catch PNG errors. Yuk.
*/
if( setjmp( write->pPng->jmpbuf ) )
return( -1 );
for( i = 0; i < area->height; i++ )
write->row_pointer[i] = (png_bytep)
IM_REGION_ADDR( region, 0, area->top + i );
png_write_rows( write->pPng, write->row_pointer, area->height );
return( 0 );
}
/* Write a VIPS image to PNG.
*/
static int
write_vips( Write *write, int compress, int interlace )
{
IMAGE *in = write->in;
int i, nb_passes;
assert( in->BandFmt == IM_BANDFMT_UCHAR );
assert( in->Coding == IM_CODING_NONE );
assert( in->Bands > 0 && in->Bands < 5 );
/* Catch PNG errors.
*/
if( setjmp( write->pPng->jmpbuf ) )
return( -1 );
/* Check input image.
*/
if( im_pincheck( in ) )
return( -1 );
if( compress < 0 || compress > 9 ) {
im_error( "im_vips2png",
"%s", _( "compress should be in [0,9]" ) );
return( -1 );
}
/* Set compression parameters.
*/
png_set_compression_level( write->pPng, compress );
write->pInfo->width = in->Xsize;
write->pInfo->height = in->Ysize;
write->pInfo->bit_depth = (in->BandFmt == IM_BANDFMT_UCHAR ? 8 : 16);
write->pInfo->gamma = (float) 1.0;
switch( in->Bands ) {
case 1: write->pInfo->color_type = PNG_COLOR_TYPE_GRAY; break;
case 2: write->pInfo->color_type = PNG_COLOR_TYPE_GRAY_ALPHA; break;
case 3: write->pInfo->color_type = PNG_COLOR_TYPE_RGB; break;
case 4: write->pInfo->color_type = PNG_COLOR_TYPE_RGB_ALPHA; break;
default:
assert( 0 );
}
png_write_info( write->pPng, write->pInfo );
/* If we're an intel byte order CPU and this is a 16bit image, we need
* to swap bytes.
*/
if( write->pInfo->bit_depth > 8 && !im_amiMSBfirst() )
png_set_swap( write->pPng );
if( interlace )
nb_passes = png_set_interlace_handling( write->pPng );
else
nb_passes = 1;
/* Write data.
*/
for( i = 0; i < nb_passes; i++ )
if( im_wbuffer( write->tg, write_png_block, write, NULL ) )
return( -1 );
/* The setjmp() was held by our background writer: reset it.
*/
if( setjmp( write->pPng->jmpbuf ) )
return( -1 );
png_write_end( write->pPng, write->pInfo );
return( 0 );
}
/* Write a VIPS image to a file as PNG.
*/
int
im_vips2png( IMAGE *in, const char *filename )
{
Write *write;
int compress;
int interlace;
char *p, *q;
char name[FILENAME_MAX];
char mode[FILENAME_MAX];
char buf[FILENAME_MAX];
if( !(write = write_new( in )) )
return( -1 );
/* Extract write mode from filename and parse.
*/
im_filename_split( filename, name, mode );
strcpy( buf, mode );
p = &buf[0];
compress = 6;
interlace = 0;
if( (q = im_getnextoption( &p )) )
compress = atoi( q );
if( (q = im_getnextoption( &p )) )
interlace = atoi( q );
/* Make output.
*/
#ifdef BINARY_OPEN
if( !(write->fp = fopen( name, "wb" )) ) {
#else /*BINARY_OPEN*/
if( !(write->fp = fopen( name, "w" )) ) {
#endif /*BINARY_OPEN*/
write_destroy( write );
im_error( "im_vips2png", _( "unable to open \"%s\"" ), name );
return( -1 );
}
png_init_io( write->pPng, write->fp );
/* Convert it!
*/
if( write_vips( write, compress, interlace ) ) {
write_destroy( write );
im_error( "im_vips2png", _( "unable to write \"%s\"" ), name );
return( -1 );
}
write_destroy( write );
return( 0 );
}
#endif /*HAVE_PNG*/